Rectifier



Patented July '12, 1932 UNITE STATES CHARLES LEO FITZ AND LEO BACHBUBER,OF MAYVIIiLE, WISCONSIN RECTIFIER Application filed September 9, 1927.Serial No. 218,521.

This invention relates to certain novel improvements in rectifiers andparticularly to devices employed to change single phase alternatingcurrent into unidirectional current.

The salient object of our invention is to provide a device of thischaracter in which the current of single phase circuit may be directedthrough a system of circuits ar- .10 ranged to change the phase of theimpressed current so as to produce a substantially polyphase outputcurrent.

Another object of the invention is to provide a transformer hook-up uponwhich the output current may be impressed to change the value of theimpressed voltage.

A further object of the invention is to so arrange the device that theoutput current may be led to current rectifiers, preferably 29 of thefull wave type, but other improved type may be employed.

A still further object of the invention is to arrange the device in sucha manner that a multiplicity of voltages may be supplied by the device.

Other objects will appear hereinafter.

The invention consists in the novel combination and arrangement of partsto be hereinafter described and claimed.

The invention will be best understood by reference to the accompanyingdrawing, showing the preferred form of construction and in which:

Fig. 1 is a schematic wiring diagram of one form of our invention asapplied to pro duce a three phase system;

Fig. 2 is a view, similar to Fig. 1, showing the invention as used toproduce a two phase system; and

Fig. 3 is a schematic view illustrating one form of construction for theinvention as used to produce voltages of different values.

The particular adaption of our invention as shown in the drawing is foruse in conb nection with any of the well-known types of radio receiversand while this is a preferred use it is to be understood that theinvention is capable of many other uses, all of which arewithin thepurview of our invention. In the mentioned use of our device; namely, in

connection with radio receivers, it is necessary that independentcircuits for supplying voltages of different values be provided; suchas, for example, a relativelyv high voltage for the plate circuits ofthe receiver, known as the B voltage, and a relatively low voltage forthe filament'circuits, or the so-called A voltage. Voltages and circuitsother than those named are often required and it is to be understoodthat these may be provided in the manner pointed out hereinafter andthat such additional circuits are within the scope of our invention.

As is well known alternating current may be symbolized by the sine wave,which represents two zero potentials and a maximum positive and amaximum negative and this is called a cycle. Polyphase is a term that isapplied when a plurality of potentials are 1mpressed in a cycle so as toproduce more than the above named varied potentials. Thus in a so-calledthree phase circuit, a cycle comprises three maximum positives, threemaximum negatives, and six zero potentials. The problem of producinguni-direction current from alternating current consist-sin altering thewave to eliminate or transpose all portions of the wave on one side ofthe zero line. Full wave rectifiers of the single-phase type usuallytranspose one portion of the wave so as to produce two pulsations in thesame direction and also to pro-duce twozero potentials. In polyphasecycles thev sine waves are disposed to occur at varied times which areexpressed as angles and which are said to lead or lag in respect to agiven wave and thus the sine waves intercross. Thus, if in a three phasecycle, one portion of the wave'sis transposed, the zero potentials maybe eliminated and a substantially straight line current may be produced.H 1

With the foregoing in mind and in accordance with the above namedobjects, we provide the following structure. Referring to Fig. 1 it maybe seen that we utilize a single phase alternating current circuitcomprising leads 10 and 11 which are connected to any suitable sourceof'powersuch, as an alternator. A transformer structure 12 islprovided.The deviceas depicted in Fig; 1 is adapted for use as a three phasedevice. The transformer structure 12 is, in the present instance, staror Y connected but if desired the well-known delta connection may beemployed. The transformer structure 12 may be either a polyphasetransformer or three single phase transformers, as is understood in theart.

In the present instance the transformer structure 12 includes threecores, 13, 14, and 15. Associated with the core 13 in the wellknownmanner, is a primary winding 16 and a secondary winding 17 and with core14 is primary winding 18 and secondary winding 19, while with core isthe primary winding 20ajnd the secondary winding 21. As stated,the'transfoimer structure 12 is star connected and therefore one end ofthe windings 16, 18, and-scare interconnected as indicated at 22.

The'open'e'nd'of winding 16 is connected to le'ad ll'by a'c'o'nductor 23in which a resistance is provided. The open end of winding 1'8 isconnected to lead 10 by a conducto'r 25*in which a condenser 26 isprovided. The open end of'winding 20 is connectedtoleadlO by aconductor27 in which an inductance 28 is-provided.

Assuming the potential passing resistance 24-to-bethemid eur'vein athree phase cycle, or phase A, the potential passing through conductor25,-d ue to the characteristics of the condenser- 26, will lead inphase, with respect to the potential in phase A and'thus produce hase'B.The potential in conductor 27 will 'e' caused to lag'the potential inphase A, dueto the chara'cteristics of inductance 28, and thus "prod-usephase G. The values or "an le of lead andlagwill be controlled'by the'appiirtenance causing the variation. Thus-a substantially'threephasecycle is produc'ed from single phase. Due to inherent structuraldifiiculties, thecurve variation will not be t'rul-y'three phase, butwill be close encugh to produce the desired action.

The secondaryl9 is connected to the anodes of a rectifying device 29 ofapproved form by wires30 'a'nd 31. The secondary winding 17 is-similarlyconnected to rectifier 32 by wires "33'a'nd 34and the secondary winding21 i'sconne'ctedto a r'e'ctifier 35 by wires 35 and 36. A'conductor 37is attached to the midpoint-of w-indi'ng 17, a conductor 38 is attachedto the midpoint of winding19, and a conductor '39is attached to themidpoint dwindling-21. The conductors 37, 38, and 39 are attachedto the"negative output conductor 40. A conductor 41 is 1 connected to thedelivery terminal of rectifier 29, a conduc'tor 42 is connected tothe-delivery terminal of rectifier 3 2, and aconductor 43 is connectedto the delivery terminal of rectifier 35. The conductors41, 42, and 43are connected to theipositive output wire 44.

In operation, fwhenthe potential in phase B isre'ceding'from the crest,the Potential in phase A is ascending, and therefore, when the potentialin phase B drops to a predetermined low point the eflectivenesstherefore will be superseded by the potential in phase A. The same istrue between phase A and G and C and B. Therefore the input into wire 44will be unidirectional and of a substantially constant amount. Thenegative potential is derived as stated. Thus a substantially directcurrent is obtained.

The structure just described is one in which but a single voltage isderived from the device. In Fig. 3 various methods of securing dilferentvoltages are shown. The above described hook-up is depicted as well asthe following.

Secondary windings 45, 46, and 47 are shown in association with cores13, 14, and 15. One end of winding 45 is connected to one end of winding46 and the other end of winding 46 is connected to one end of winding47. The free ends of windings 47 and 45 are connected to output wires 49and 50 whichare directed to a suitable point either for rectification oruse. The windings 45, 46, and 47 are obviously connected in series whilein the foregoing description the windings were connected in parallel.

Three secondary windings 51, 52, and 53 are associated with the cores13, 14, and 15 respectively. These windings are connected in series andthe ends thereof are connected to a suitable rectifier 54, which, asdepicted, is of the filament type. The midpoint of the windings istapped as at 55 and the negative lead 57 is connected thereto. Thepositive lead 56 is connected as shown. The filament 58 derives currentfrom the secondary windings 59, 60, and 61. Thus, a plurality ofvoltages may be derived from the device for use in connection or withradio receivers. It is to be understood that the foregoing connectionsneed not be strictly adhered to for any of the foregoing may be usedthroughout and the different hook-ups described are shown merely forpurposes of illustration.

The foregoing description relates to three phase connections but a twophase cycle may alsobe used as shown in Fig. 2. While this will not givea current as smooth and unvarying as three phase, it will obviously bebetter than one phase.

In Fig. 2 the line wires 10 and 11' are connected to suitable source ofsingle phase alternating current. A transformer structure 62 is providedwhich includes two transformers having cores 63 and 64. Primary windings65 and 66 are associated with the cores 63 and 64 in the well knownmanner as are secondary windings 67 and 68. One end of each of theprimary windings 65 and 66 are connected as at 69.

A lead 7 O connects the free end of winding 66 to wire 10. A conductor71 connects the free end of winding 65to wire 10 and an inductance 72and a resistance 7 3 are protance therein and being connected to saidlast vided in conductor 71. A conductor 74 is connected to the commonwire 69 and a resistance 75 is provided in this conductor.

The leads 76 and 77 of the secondary winding 67 are connected to theanodes of a rectifier 78 and the leads 79 and 80 of winding 68 aresimilarly connected to a rectifier 81. The output lead 82 of rectifier78 and the output lead 83 of rectifier 81 are connected to the positiveoutput lead 84. A lead 85 is connected to the midpoint of winding 67 andlead 86 is connected to the midpoint of winding 68 and these leads areconnected to the negative output wire 87.

The potential in lead 74 may represent phase A and the potential inphase B, in lead 71, will be caused to lag behind phase A due to thecharacteristics of the appurtenances in this lead. The rectifyingdevices 78 and 81 will act to transpose part of the wave and thus aunidirectional current is obtained in the output which will be nearly astraight line potential for as the potential in phase A drops from thecrest the potential in phase B is ascending and when the potential inphase A reaches a predetermined low point the potential in phase B willsupersede it, and the reverse is true of phase B and phase A.

Therefore a unidirectional current embodying the characteristicsdescribed is obtained.

From the foregoing it is apparent that We have provided a device whichwill very effectively eliminate the pulsations so characteristic ofrectified single phase alternating current. Further, the device will besimple in construction and operation and expensive devices now requiredfor rectifying alternating current will be eliminated.

l/Vhile we have illustrated and described the preferred form ofconstruction for carrying our invention into effect, this is capable ofvariation and modification, without departing from the spirit of theinvention. e, therefore, do not wish to be limited to the precisedetails of construction set forth, but desire to avail ourselves of suchvariations and modifications as come within the scope of the appendedclaims.

Having thus described our invention what we claim as new and desire toprotect by Letters Patent is:

1. A transformer structure comprising a core structure, primary windingsassociated with said core structure, conductors connected to a source ofsingle phase alternating current, one of said conductors having acondenser therein, means for connecting said last named conductor to thefree end of one of said primary windings, means for interconnecting saidlast named conductor and the free end of another of said primarywindings, said last named means having an inducnamed conductor ahead ofsaid condenser, the other of said conductors having a resistance thereinand being connected to the free end of another of said primary windings,secondary windings associated with said core structures and said primarywindings, said secondary windings having the ends thereof connected tothe anodes of rectifying devices, the output leads of said rectifyingdevices being connected to a common conductor to provide the positiveterminal for a unidirectional current supply, a negative conductor forsaid unidirectional current supply connected to the midpoints of saidsecondary windings, other secondary windings connected in series witheach other and to the anodes of a rectifying device, a filament for saidlast named rectifying device, windings associated with said corestructure for supplying current to the filament of said rectifyingdevice, a conductor connected to the output of said rectifying devicefor supplying a positive unidirectional current, and another conductorconnected to the midpoint of one of said last named secondary windingsfor supplying a negative unidirectional current.

2. A translating system for obtaining from a single phase alternatingcurrent source a smooth direct polyphase current, and for obtainingdifferent potentials from the polyphase current, comprising atransformer structure including interconnected primaries connected tothe current source, and means in the primaries for effecting phasedisplacement of the current supplied thereto, means for rectifying thesecondary currents into unidirectional current and for combining thepulses thereof into overlapping pulses, secondaries connected in serieswith each other and to the anodes of a rectifying device, and othersecondaries for supplying current to the filament of said rectifyingdevice, a conductor tapped from the mid-point of one of said first-namedwindings for supplying a negative direct current, and another conductorconnected to the output of said rectifying device for supplying apositive direct current.

In testimony whereof we affix our signatures.

CHARLES LEO FITZ. LEO BACHBUBER.

